Refinery processing of whole crudes involves processes to form multiple products, with each product potentially requiring a separate multi-stage process. Selecting a crude slate for a refinery can require balancing the needs of the various multi-stage processes to improve the overall profitability of the refinery. Due to the large number of potential interactions between a crude slate and the various processes, altering a crude slate to attempt to take advantage of changes in price relationships between crude oil sources can pose significant risks.
Even within a single process train for forming products, it can be difficult to determine whether a variation in process conditions will be beneficial. A process operator may be able to monitor the direct benefits of a process change for a desired product, but a typical process train can also generate a variety of side products. The information to determine whether debits in side products outweigh the benefits to a primary product may not be readily available for a process operator.
U.S. Pat. No. 7,949,417 describes a model predictive controller solution analysis process. The solution from a multivariable predictive controller is analyzed and described by providing quantitative input to operators regarding the effect of changing controller limits on the controller solution. This information allows rapid operator response to changes and more optimal process operation.